markdown-it Subscript Plugin

markdown-it-sub is a specialized plugin designed for the popular markdown-it parser, extending its capabilities to render subscript `<sub>` HTML tags from specific Markdown syntax. It adopts a Pandoc-like markup convention, where content enclosed in tildes (e.g., `H~2~O`) is parsed and converted into a subscript element. The current stable version is 2.0.0. While an explicit release cadence is not provided, markdown-it plugins typically maintain long-term stability and are updated primarily in response to breaking changes within the core markdown-it library or critical bug fixes. Its primary differentiator is its focused functionality on subscript rendering, offering a lightweight and standards-compliant method for incorporating mathematical or chemical notations without the complexity of full-fledged LaTeX-like rendering engines. It integrates seamlessly into existing markdown-it setups, enhancing parsing capabilities with minimal overhead. The plugin does not currently support nested subscript markup.